A 315- $\varOmega$ Resistor Is Connected in Series with a Parallel-Plate Capacitor Across

Multiple Choice

A 315- $\varOmega$ resistor is connected in series with a parallel-plate capacitor across the terminals of a 60.0-Hz ac generator. When the gap between the plates is empty, its capacitance is 2.65 µF. Determine the ratio of the rms current in the circuit when the capacitor is empty to that when ruby mica ( $\kappa$ = 5.40) is inserted between the plates?

A) 2.87
B) 2.32
C) 0.430
D) 0.348
E) 0.253